True spasms when corrected gain acceptance (4,6)
I believe the answer is:
'gain acceptance' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'true spasms when corrected' is the wordplay.
'when corrected' indicates an anagram.
'truespasms' with letters rearranged gives 'PASS MUSTER'.
Can you help me to learn more?
(Other definitions for pass muster that I've seen before include "Satisfy, suffice" , "To fit the bill" , "Be good enough" , "appear acceptable" .)